[illitirit]

I am new to the headphone arena, and audio for that matter.
 
I want to know why the sound quality of a expensive headphone matters when equalizing could be done to the headphone.
 
 
Take for example :
 
LCD2   and    HD800.
 
 
The lcd2 is known for being warm and having a rolled off treble, whereas the HD800 has a bright sound and less bass.
 
 
 
Couldnt I just EQ either headphone to be the same as the other?   
 
I am trying to understand why the base sound qualities of each headphone matter when an equalizer seems like it could shift the primary sound of any headphone to what you want it to sound like considering the headphone driver is capable of producing said frequencies. 

 

[Sefelt103]

I am sure you can buy high grade equalisers these days with minimal distortion provided you don't want to make too drastic a change. The design of the headphone primarily affects its acoustics, equalising though it will make a noticeable difference obviously does not alter the fundamental design of the headphone. So you could try to equalise an LCD 2 to make it sound like Sennheiser's HD800 or vice-versa but I would be surprised if equalisation could make them indisinguishable in blind tests. How a headphone sounds is determined by dimensions, driver characteristics and the earcup and earpads. Equalisation is a useful tool but it is inherently limited. I am not particularly a fan of equalisation as I see it as another addition of distortion to go with warm op-amps and colourful amplifiers and headphones.

 

[TMRaven]

EQ only affects tonal balance, but that's not all there is to a headphone's sound.  There's low distortion you have to worry about, minimal resonance problems, soundstage and imaging size, unforced and effortless bass extension, and more.  My methodology of going about it revolves around getting the best sounding, most realistic and neutral headphones I can find that suits my tastes, then slightly EQ it accordingly to make up for any drawbacks.  
 
On a less drastic note of the HD800 vs the LCD2 (which you will never even begin to make sound like each other), I took a Hifiman HE-400 and LCD2 and EQ'd the HE-400 to the best of my ability to sound like the LCD2.  I did get the tonality close, but the LCD2 was forever thicker and rounded sounding, while the HE-400 was forever thinner and airier sounding.

 

[fjrabon]

TLDR version:
 
1) It actually takes a pretty good headphone to respond well to EQ without causing it to lose soundstage and resolving ability.  And it especially takes a really good EQ.
2) EQ can't improve detail resolution and sound stage (seeing point one, it can really only make it worse).
 
You can think of headphones having a few primary characteristics on a physics level that play out in different ways:
 
1) the ability of the driver to move quickly enough to reproduce the source accurately as possible.  
2) the ability of the driver to equally provide the same force across the spectrum.
3) The enclosure's resonances
4) the degree to which the two parts are matched
 
How these interplay create 90% of the headphone's characteristics.  
 
One aspect of the resulting sound is frequency response.  That is the degree to which a headphone sounds bassy, or neautral, or midrange heavy, or whatever else.  It's the easiest aspect of a headphone to characterize, and many refer to this as the headphone's "sound signature."  EQ can certainly level the playing ground here a lot, especially a really good EQ.  However, EQ shouldn't be looked at as a "fixer of cheap headphones" for several reasons.  First, to get a good one, good enough to accurately get back to the sound signature you're after, it will often cost more than simply buying the headphone sound you're after int he first place.  Secondly, often times as you push a mediocre to headphone in ways it isn't adept, bigger issues come to the fore.  For instance, if you try to EQ in significant bass to the KSC75s, they can't handle this additional power load very well, and they just get indistinct and sound like skullcandys.  So, ultimately, those headphones that are best able to handle an EQ adjustment with ease are, unfortunately, the headphones you don't really need to EQ in the first place.  I have a pretty good EQ unit in my home system, and when it's in front of my amp and Grado SR225s, I can reshape the Grado's sound pretty easily, with little/no loss in sound quality.  But if I try to put an EQ in front of my unamped KSC75s, as soon as I make almost any adjustments with the EQ, things start to fall apart.  The KSC75s lose their definition, the sound stage narrows, bass gets muddy.  Same when I try to EQ more bass into my AT AD700s, they just can't deal with it, and all the reasons I liked the headphone in the first place, the soundstage and detail resolution, fall apart in a hurry.  I'm a believer that almost all headphones should be EQ tuned, based on both the headphone, but also your own personal ear characteristics.  But that isn't a license to expect miracles from mediocre gear, if anything doing this is actually requires better gear, not worse.  
 
Now, even if you do get a headphone and EQ it up, and it works out alright, that isn't all there is to a headphone either.  There's also detail resolution and soundstage.  Detail resolution is a combination of the driver's speed and internal resonances.  You aren't fixing those at all with EQ.  Soundstage has to do with how well the drivers are matched, how they are angled at your ear, and the frequency response at the upper ultra high frequencies (and the headphone's ability to enhance or dull quick contrasts in these ultra high frequencies).  Again, EQ is of little/no use here.  To some degree you can bring a headphone "forward" or "back in soundstage with an incredible EQ adjusting the ultra high frequencies, the so called presence frequencies, but you can do very little to make it wider, which usually has to do with resonances, enclosure symmetry and driver matching

 

[alpha80]

I am new to the headphone arena, and audio for that matter.

I want to know why the sound quality of a expensive headphone matters when equalizing could be done to the headphone.


Take for example :

LCD2   and    HD800.


The lcd2 is known for being warm and having a rolled off treble, whereas the HD800 has a bright sound and less bass.



Couldnt I just EQ either headphone to be the same as the other?   

I am trying to understand why the base sound qualities of each headphone matter when an equalizer seems like it could shift the primary sound of any headphone to what you want it to sound like considering the headphone driver is capable of producing said frequencies. 

Because even the best digital EQ's (my favorite being FabFilter's Pro-Q2 which i happily use and abuse constantly at work), still can't do too much without introducing unwanted things to the signal, and this result is magnified exponentially when applying lesser digital EQ's to lower fidelity digital audio.

For instance, I work mostly at 24bit, either 192khz sampling Rae or 96khz sampling Rate. Pro-Q sounds great at that resolution.

But if one is tweaking with these consumer level digital EQ's, on cd-Quality audio (16bit, 44khz), the signal can really take a huge hit quality wise in the tweaked portions. And I don't even want to hear what it would do to an MP3 at 128kbps

 

[illitirit]

hmm interesting.
 
So i gather from what you guys are saying is that no matter what, the acoustic characteristic of each headphone cannot be changed.  Is this mostly related to terms I hear like timbre and voicing?
 
Also that EQ can dirty the signal alot?

 

[TMRaven]

EQ doesn't really dirty up the signal, no.  At its worst it will just be slightly inaccurate if you're dealing with something like a graphic EQ with limited bars.

 

[alpha80]

  EQ doesn't really dirty up the signal, no.  

HAHAHAHAHAHAHAHAHAHA.
If you only knew, brother!
The amount of artifacts introduced would make you chart/graph lovers cringe!

 

[JaZZ]

  HAHAHAHAHAHAHAHAHAHA.
If you only knew, brother!
The amount of artifacts introduced would make you chart/graph lovers cringe!

 
Explain!

 

[alpha80]

Blackhawks are playing dude.
I'll come back to this tomorrow, but all distortion is not equal.
Analog harmonic distortion is actually what makes music sound "warm/sweet/musical/natural/magical"
This is what valves and tubes introduce, op amps etc.  and why certain vintage outboard equipment sounds so "good"
Digital distortion is inharmonic, and godawful.  Truncation distortion equally bad.
 
We record at 24bit depth, and many times greater sample rate than CD quality, nowadays for this specific reason, and use algorithms with extreme oversampling like FabFilter Pro-Q2, but they are very overbuilt, software wise, and use huge amounts of CPU power compared to the consumer equivalent.  Consumer digital EQ's lack dynamic range, don't have quality anti-aliasing, and introduce significant amounts of non-harmonic, and non-linear distortion.  Many don't take care to take into account all the amplitude and phase
characteristics of the analog equivalents they aim to emulate.
 
And all these nasty artifacts increase exponentially with lower sample rates, like CD quality or god forbid MP3's.

 

[TMRaven]

Do yourself a favor OP, and let your own ears decide if the EQ is affecting your sound quality or not.
 
I've owned my fair share of very revealing headphones, and for what it's worth, minimal EQ'ing never muddied the sound or made things sound worse through the headphones, it only made them better.
 
Many of the prevalent issues surrounding the most popular headphones on head-fi were mostly cured with some minimal EQ.  A treble rolloff for the HE-400, a 4khz reduction for the HE-560, a 3db shelf in the treble for the HD-800, a 3db hump in the lower treble for the LCD-X; applying small amounts of EQ to fine-tune headphones that already sound good helps them sound even better.

 

[alpha80]

Do yourself a favor OP, and let your own ears decide if the EQ is affecting your sound quality or not.

Applying small amounts of EQ to fine-tune headphones that already sound good helps them sound even better.

Fully areed on these parts of your post.

@OP, find a headphone and source and amp setup which sounds the absolute closest to what YOU LIKE. Then as listening to your favorite stuff, small tweaks to areas you find troublesome (and they will be there, no phone is yet perfect), will help you enjoy your music more.

If you're not using these for anything more than personal enjoyment, pay no mind to all us extremists ! Or it'll COST you !

 

[ProtegeManiac]

  I am new to the headphone arena, and audio for that matter.
 
I want to know why the sound quality of a expensive headphone matters when equalizing could be done to the headphone.
 
Take for example :
 
LCD2   and    HD800.
 
The lcd2 is known for being warm and having a rolled off treble, whereas the HD800 has a bright sound and less bass.
 
Couldnt I just EQ either headphone to be the same as the other?   
 
I am trying to understand why the base sound qualities of each headphone matter when an equalizer seems like it could shift the primary sound of any headphone to what you want it to sound like considering the headphone driver is capable of producing said frequencies. 

 

First off, there is no user-accessible EQ that can completely alter the sound of a headphone to make it completely flat or sound exactly like another headphone or speaker. You have to understood how EQ works: for starters, even if you have a 30-band graphic EQ, do all of those frequencies correspond to all the frequencies that you need or want to tweak? If it was parametric, you still have to take into account a few other realities of EQ, primarily the Q-factor, or the width of the effect on the frequency spectrum. If you have a headphone or speaker with a narrow dip centered at 4khz and then followed by a narrow peak at 6khz, that's not an easy fix - you can't set the Q-factor narrow enough for you to be able to fill up from 4khz without adding to the nearer frequencies up to 7khz. A too narrow setting even if available on your EQ program/hardware will sound unnatural. EQ is not a magic cure-all - even in car audio EQ follows time alignment (and crossovers) on the list of important DSP functions, and even then this is preceded by proper speaker installation. You can't just DSP your way out of an ultimately flawed installation, and this is an application where there is barely any debate on whether to use EQ or not. On top of that, EQ doesn't have the same effect, particularly when boosting frequencies. As an extreme (ie most obvious) example, if all it took was boosting frequencies then nobody would need subwoofers either, all they had to do was apply huge bass boost on their TV speakers. Buy a nice action BluRay, try it on the Bass EQ on your HDTV, your 2.0 or even 2.1 speakers with a graphic EQ on the player, then try it on an LCD-2 and then an HT system with no bass boost and the subwoofer gain set to a level that just keeps up with the mains - you'll see what I mean.

 

Second, let's say you have an EQ that you can fully customize instead of one with a user-accessible interface. There's already an app for that - it's called Accudio and it's on iOS. The problem there is that even if you have such an EQ you still can't magically make an HD650 totally sound like an HD800 because there are a lot of things that affect the measurable response that can't just be replicated by EQ (and vice versa). For one thing, there's driver placement, and how they affect imaging/soundstage. In the quickie diagram I did on Paint (see below), the driver placement on the HD800 has a toe-in angle that affects how it images every sound source, or at least tries to barring what speakers really do with these, while the HD6x0 only naturally develops a slight angle (and even then not everyone actually wears them that way) and they're still too close to the opening of the ear canal. While response does affect imaging, like how bass boost can push the bass drum and guitar forward closer to if not between your head and the vocalist, that doesn't necessarily mean that you can easily override the imaging of the HD800 to make it "image" like the HD6x0. Similarly, in a home system, you have a bit more wiggle room increasing the gain on the subwoofer if you have it much farther back than the speakers and won't be reinforced (and muddied) by walls (and corners) without acoustic treatment that will just bounce them around (on the opposite end, in a car you have the least wiggle room, since conventionally the subwoofer is in the rear luggage comparment, and no time alignment/delay profile can completely obliterate that). The HD800 and HD650 imaging is basically the same as using a neutral-tuned 3-way, 4-driver tower speaker with the proper toe-in angle vs a standmount with an upper bass boost but has a higher -3db roll-off point set closer together with barely any toe-in (note that in some cases, depending on the dispersion width, this may be beneficial to certain speakers) - boosting the lowest frequencies on the latter will likely distort the bass through cone break up if not overexcursion while still sounding relatively congested and imprecise. 

To make the non-effect more obvious, try Accudio on a system using an iOS device as a source, but outputs digital audio so we can eliminate the possibility of distortion from how the iDevice may drive one headphone much better than the other, and then try the app on the HD800, K701, SR225, and HD650.

 

Left: top view diagram, HD800 in red and HD650 in gray; triangles=main vocals, rectangles=lead, rhythm, and bass, circles=drums (apologies if it looks confusing, but it's a lot easier to illustrate when you have them overlaid)

Right: side view of human head with HD6x0 driver and HD800 drivers shown relative to ear

 

 

 

Add to that some inherent driver design differences when you compare different types of drivers. If you want really loud bass, then there's no beating a dynamic driver, which is why nearly all subwoofers are made of this design, even if the response may not be completely flat, these are frequencies where, on their own (if you set the gain relative to the mains amp right) non-linearities are very, very difficult to notice; if you want bass that measures really flat, you'd have to use planars. The problem there is that because of the lack of excursion they need to compensate with surface area a lot more, while at the same time using a large dynamic driver to get more low bass tends to have penalties to its capabilities for higher frequencies (size is relative to application, so you can't compare a 70mm FR driver to a 7in midwoofer, given the distance they're meant to be used by listeners). Also while a long excursion makes for louder bass, that also means more cone break-up, so they have to design it to be stronger to reduce distortion throughout the range as well as a larger magnet to control it better, which adds weight and may even affect efficiency.

 

 
Also that EQ can dirty the signal alot?

 
If it's a really crappy EQ then yes, otherwise digital EQs don't add any audible noise and just depends on how much or how badly they're used. Used judiciously, there wouldn't be any problem.

 

[achristilaw]

EQ is for people without money and an ear.....

 

[tomb]

Some great responses here.  I won't add to most of the discussion about artifacts or inaccuracies in the equalization, the effects on the headphone, etc.
 
One simple problem is the amp (wherever and in whatever component it might be).  Anything more than a few tweaks around the edges and your amp may be hitting its limits very quickly.  Still, if a little bit of adjustment makes you happy, go for it.